I may not have children but I can relate to so much of this. When my ex and I split up and I lived by myself with the 2 dogs, although technically I was responsible for all the chores. I had more time, more head space. Things didn't not get done that someone said they would do. It freed up so much emotional space. Coming home to a clean house was a dream.
Sounds like you had 3 children. So glad to hear you are embracing the levity of your new rhythm.